Boil it in water slowly until it's either falling off the bone or the string holding it together is not doing a good job anymore.  You'll need to put it in a pan, cover with cold water so it's at least 1 inch covered.  For every pint of water, add a good tablesppon of honey and half a tablespoon of English mustard.

Once cooked, remove the ham from the pan and keep the water.  Skim off excess scummy fat floating on the surface, then use the water to cook cabbage in.

Slive the ham really thin once it's rested a bit, and serve with mashed potato and the cabbage.